UE5.3 C++ Ceiusm中的POI 制作3DUI 结合坐标转化

一.核心思路WidgetComponent + CesiumGloberAnchor

二.先制作POI

创建C++ Actor来制作，APOI。直接上代码

#pragma once#include "CoreMinimal.h"
#include "GameFramework/Actor.h"
#include "CesiumGlobeAnchorComponent.h"
#include "POI.generated.h"UCLASS()
class HMS3DUI_API APOI : public AActor
{GENERATED_BODY()public:	// Sets default values for this actor's propertiesAPOI();protected:// Called when the game starts or when spawnedvirtual void BeginPlay() override;public:	// Called every framevirtual void Tick(float DeltaTime) override;UFUNCTION(BlueprintCallable)void MoveToLLA(double Longtitude,double Latitude,double Altidude);UFUNCTION(BlueprintCallable)FVector GetLLA();// WidgetComponentUPROPERTY(BlueprintReadWrite,EditAnywhere, Category = WidgetComponent)class UWidgetComponent* WidgetComponent;
private:UPROPERTY(BlueprintReadOnly, EditAnywhere, meta = (AllowPrivateAccess = "true"))UCesiumGlobeAnchorComponent* globeAnchor;//地球组件
};

然后在CPP里，实现组件。并设置为3DUI,这里用的屏幕尺寸的。

// Sets default values
APOI::APOI()
{// Set this actor to call Tick() every frame.  You can turn this off to improve performance if you don't need it.PrimaryActorTick.bCanEverTick = true;WidgetComponent = CreateDefaultSubobject<UWidgetComponent>(TEXT("WidgetComponent"));WidgetComponent->AttachToComponent(RootComponent, FAttachmentTransformRules::KeepRelativeTransform);// 设置控件蓝图//UClass* Widget = LoadClass<UUserWidget>(NULL, TEXT("/Script/UMGEditor.WidgetBlueprint'/HMS3DUI/POI.POI_C'"));static ConstructorHelpers::FClassFinder<UUserWidget>WidgetClass(TEXT("/Script/UMGEditor.WidgetBlueprint'/HMS3DUI/POI.POI_C'"));WidgetComponent->SetWidgetClass(WidgetClass.Class);//设置渲染方式,是渲染到屏幕还是世界中WidgetComponent->SetWidgetSpace(EWidgetSpace::Screen);//设置绘制大小WidgetComponent->SetDrawSize(FVector2D(1280, 720));globeAnchor = CreateDefaultSubobject<UCesiumGlobeAnchorComponent>(TEXT("CesiumGlobe"));
}

两个函数，无论时显示UI现在的地方，还是UI输入去其它地方都能实现，坐标的转换。

void APOI::MoveToLLA(double Longtitude, double Latitude, double Altidude)
{globeAnchor->MoveToLongitudeLatitudeHeight(FVector(Longtitude, Latitude, Altidude));
}FVector APOI::GetLLA()
{FVector tmp = globeAnchor->GetLongitudeLatitudeHeight();if (globeAnchor){return tmp;}return FVector(0,0,0);
}

简单做个UI,这个UI把锚点放到屏幕中心。就能实现3DUI刚好在那个点上。

通过UIManager, Spawn和管理3DUI.

void AHMSUIManager::Spawn3DUI(double Longtitude, double Latitude, double Altidude)
{/*UClass* MyTmpClass = LoadClass<AActor>(this, TEXT("/Script/Engine.Blueprint'/HMS3DUI/BP_POI.BP_POI_C'"));if (MyTmpClass){AActor* SpawnActor = GetWorld()->SpawnActor<AActor>(MyTmpClass, FVector::ZeroVector, FRotator::ZeroRotator);}*/UClass* MyTmpClass = LoadClass<APOI>(this, TEXT("/Script/Engine.Blueprint'/HMS3DUI/BP_POI.BP_POI_C'"));APOI* poi = GetWorld()->SpawnActor<APOI>(MyTmpClass);poi->MoveToLLA(Longtitude, Latitude, Altidude);
}

简单的通过UI,传值调用。

这里当时卡住了，我继承了C++类来进一步写POI的写如UI的TEXT。获得WidgetComponet并GetWidget 转换为 POI这个Widget。这样就可以实现Actor拿到它想显示的UI,并赋值修改这个UI。

而且涉及经纬度，ToText需要设置小数点后的位数 7。

自动在对应经纬产出物体，显示经纬高

三. 延申功能，在鼠标射线中，点击的地方生成3DUI。

之所以用蓝图，因为快。C++也能写只是，要多加一些库。

核心